eosin

American  

[ee-uh-sin] / ˈi ə sɪn /

Also eosine

noun

Chemistry.

1. Also called bromeosin, tetrabromofluorescein.  a red, crystalline, water-insoluble solid, C 20 H 8 Br 4 O 5 , derived from fluorescein by bromination: used chiefly as an acid dye for dyeing silk a rose red color and as a histological stain.

2. any of a variety of eosinlike dyes.

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eosin British  

/ ˈiːəʊsɪn, ˈiːəʊsɪn, -ˌsiːn /

noun

1. Also called: bromeosin.  a red crystalline water-insoluble derivative of fluorescein. Its soluble salts are used as dyes. Formula: C 20 H 8 Br 4 O 5

2. any of several similar dyes

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Other Word Forms

• eosin-like adjective
• eosinic adjective
• eosinlike adjective

Etymology

Origin of eosin

1865–70; < Greek ēṓs dawn ( see eo-) + -in ²

Example Sentences

They are identified by their distinctive granules that stain red when treated with an acidic reagent, eosin, which gave them their name.

From Science Daily • May 22, 2024

Tissue samples were processed to paraffin wax and tissue sections were routinely stained with haematoxylin and eosin.

From Nature • Sep. 8, 2015

The granules of eosinophils stain best with an acidic stain known as eosin.

From Textbooks • Jun. 19, 2013

In the female this was dark eosin colour, in the male yellowish eosin.

From Hormones and Heredity by Cunningham, J. T.

Another factor "whiting" which produces no effect on red makes eosin entirely white.

From A Critique of the Theory of Evolution by Morgan, Thomas Hunt